This invention relates, in general, to driver circuits, and more particularly, to a high speed drive circuit capable of driving large loads on an integrated circuit.
Driver circuits sometimes called buffer circuits or buffer/drivers are widely used in digital circuits. These circuits serve not only to buffer a signal such as a clock signal from large loads but also serve to drive the large loads. As integrated circuits become more dense and larger in physical size the loads that these drivers must drive also become larger. As an example, in microprocessor designs it is common practice to interconnect an array of registers in a bus structure. This array of registers has inputs to control the logic function performed and has inputs to allow interaction with the bus. The bus is usually placed on metal lines and the register inputs are connected through polysilicon interconnect lines which are commonly called poly lines. Line driver circuits are used to provide the signals on these poly lines. These line drivers should not provide much of a delay to the signal being transferred to the poly lines and the signal being provided must have an amplitude as near the power supply voltage as possible.
Accordingly, it is an object of the present invention to provide an improved driver circuit.
Another object of the present invention is to provide a driver circuit capable of operating at high speeds and providing an output signal having an amplitude substantially equal to the power supply voltage of the circuit.
Yet another object of the present invention is to provide a high speed driver circuit which provides a reduced amount of loading to the signal being processed by the driver circuit.